// -------------------------------------------------
// BlinKit - BlinKit Library
// -------------------------------------------------
//   File Name: style_rule_import.cpp
// Description: StyleRuleImport Class
//      Author: Ziming Li
//     Created: 2021-07-29
// -------------------------------------------------
// Copyright (C) 2021 MingYang Software Technology.
// -------------------------------------------------

/*
 * (C) 1999-2003 Lars Knoll (knoll@kde.org)
 * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
 * Copyright (C) 2002, 2005, 2006, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include "./style_rule_import.h"

#include "blinkit/blink/renderer/core/css/style_sheet_contents.h"
#include "blinkit/blink/renderer/core/dom/document.h"
#include "blinkit/blink/renderer/core/fetch/CSSStyleSheetResource.h"
// BKTODO: #include "core/fetch/FetchInitiatorTypeNames.h"
#include "blinkit/blink/renderer/core/fetch/fetch_request.h"
#include "blinkit/blink/renderer/core/fetch/resource_fetcher.h"

namespace blink {

GCRefPtr<StyleRuleImport> StyleRuleImport::create(const String& href, const GCRefPtr<MediaQuerySet>& media)
{
    return GCWrapShared(new StyleRuleImport(href, media));
}

StyleRuleImport::StyleRuleImport(const String& href, const GCRefPtr<MediaQuerySet>& media)
    : StyleRuleBase(Import)
    , m_styleSheetClient(this)
    , m_strHref(href)
    , m_mediaQueries(media)
    , m_resource(nullptr)
    , m_loading(false)
{
    if (!m_mediaQueries)
        m_mediaQueries = MediaQuerySet::create(String());
}

StyleRuleImport::~StyleRuleImport()
{
    if (m_styleSheet)
        m_styleSheet->clearOwnerRule();
    if (m_resource)
        m_resource->removeClient(&m_styleSheetClient);
}

DEFINE_TRACE_AFTER_DISPATCH(StyleRuleImport)
{
    visitor->trace(m_mediaQueries);
    visitor->trace(m_styleSheet);
    StyleRuleBase::traceAfterDispatch(visitor);
}

void StyleRuleImport::setCSSStyleSheet(const String& href, const KURL& baseURL, const String& charset, const CSSStyleSheetResource* cachedStyleSheet)
{
    if (m_styleSheet)
        m_styleSheet->clearOwnerRule();

    CSSParserContext context = nullptr != m_parentStyleSheet
        ? m_parentStyleSheet->parserContext()
        : strictCSSParserContext();
    context.setCharset(charset);
    Document* document = nullptr != m_parentStyleSheet ? m_parentStyleSheet->singleOwnerDocument() : nullptr;
    if (!baseURL.isEmpty())
    {
        context.setBaseURL(baseURL);
#if 0 // BKTODO:
        if (document)
            context.setReferrer(Referrer(baseURL.strippedForUseAsReferrer(), document->referrerPolicy()));
#endif
    }

    m_styleSheet = StyleSheetContents::create(this, href, context);

    m_styleSheet->parseAuthorStyleSheet(cachedStyleSheet);

    m_loading = false;

    if (nullptr != m_parentStyleSheet)
    {
        m_parentStyleSheet->notifyLoadedSheet(cachedStyleSheet);
        m_parentStyleSheet->checkLoaded();
    }
}

bool StyleRuleImport::isLoading() const
{
    return m_loading || (m_styleSheet && m_styleSheet->isLoading());
}

void StyleRuleImport::requestStyleSheet()
{
    if (nullptr == m_parentStyleSheet)
        return;

    Document *document = m_parentStyleSheet->singleOwnerDocument();
    if (nullptr == document)
        return;

    ResourceFetcher *fetcher = document->fetcher();
    if (nullptr == fetcher)
        return;

    KURL absURL;
    if (!m_parentStyleSheet->baseURL().isEmpty())
    {
        // use parent styleheet's URL as the base URL
        absURL = KURL(m_parentStyleSheet->baseURL(), m_strHref);
    }
    else
    {
        absURL = document->completeURL(m_strHref);
    }

    // Check for a cycle in our import chain.  If we encounter a stylesheet
    // in our parent chain with the same URL, then just bail.
    StyleSheetContents *rootSheet = m_parentStyleSheet;
    for (StyleSheetContents *sheet = m_parentStyleSheet; nullptr != sheet; sheet = sheet->parentStyleSheet())
    {
        if (equalIgnoringFragmentIdentifier(absURL, sheet->baseURL())
            || equalIgnoringFragmentIdentifier(absURL, document->completeURL(sheet->originalURL())))
        {
            return;
        }
        rootSheet = sheet;
    }

    FetchRequest request(ResourceRequest(absURL), m_parentStyleSheet->charset());
    m_resource = CSSStyleSheetResource::fetch(request, fetcher);
    if (m_resource)
    {
        // if the import rule is issued dynamically, the sheet may be
        // removed from the pending sheet count, so let the doc know
        // the sheet being imported is pending.
        if (nullptr != m_parentStyleSheet && m_parentStyleSheet->loadCompleted() && rootSheet == m_parentStyleSheet)
            m_parentStyleSheet->startLoadingDynamicSheet();
        m_loading = true;
        m_resource->addClient(&m_styleSheetClient);
    }
}

StyleSheetContents* StyleRuleImport::styleSheet(void) const
{
    return m_styleSheet.get();
}

} // namespace blink
